Sulfidation of Oxidized Copper Studied by Soft X-ray Spectroscopy

Using soft X-ray spectroscopy, we have studied the reactions between Cu2O and CuO with an aqueous solution of 1mM Na2S. Exposure to dissolved sulfide for several hours clearly reduces Cu(II) to Cu(I) compounds. However, there are still strong oxygen signals in the spectra, indicating a more complex surface composition than simple copper sulfides.